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Survival of endangered fish calls for protectionHabitat preservation good for healthy river

By Ileene Anderson

The 3-inch-long, olive-gray Santa Ana sucker has inhabited the Santa Ana and San Gabriel rivers and Tujunga Wash for hundreds of thousands of years, adapting deftly to the area's episodic flooding and droughts.

But in just a few short decades, its survival has been jeopardized by staggering urban development that has dammed, diverted and polluted its native waters.

Since the 1970s, the fish has lost nearly 95 percent of its historic habitat.

The situation became so dire that in 2000, the Santa Ana sucker was listed as a threatened species under the federal Endangered Species Act.

The Endangered Species Act recognizes the importance of habitat for species.

It requires that "critical habitat" - habitat that is critical for the survival and recovery of species - be identified and designated. Once critical habitat is designated, there's a heightened level of review for any activity that might damage or destroy that habitat.

But scientific studies have determined that species that have critical habitat designated are more than twice as likely to be recovering from the brink of extinction than species with no critical habitat designated.

In 2005, the U.S. Fish and Wildlife Service identified a little more than 8,000 acres of critical habitat for the Santa Ana sucker but failed to include the Santa Ana River in the designation despite the fact that it has a successfully reproducing population of fish. The Center for Biological Diversity successfully challengedthe politically tainted and scientifically flawed designation in court, which resulted in the designation of 9,331 acres of scientifically based critical habitat in December 2010.

While this recent critical habitat designation still includes areas in the Tujunga Wash and San Gabriel River in Los Angeles County, it also includes crucial areas of the Santa Ana River and two of its tributaries - Mill and City creeks.

While obviously fish need water in order to live and reproduce, the Santa Ana sucker has additional requirements that are also included in the critical habitat designation.

The U.S. Fish and Wildlife Service rightly used verified, scientific models when it included areas of the Santa Ana River that are seasonally dry but, during the wet season, create natural hydrologic conditions that transport gravel sediments downstream that the Santa Ana sucker relies upon for successful reproduction.

Current long-term monitoring of the populations of Santa Ana sucker in the Santa Ana River have documented a decrease in both gravels and fish, highlighting the need for maintaining gravel habitat in the river for successful fish breeding.

Arguments that seasonally dry stretches of the Santa Ana River should not be included in a critical habitat designation ignore the basic biological requirements of the Santa Ana sucker.

Without sustaining the crucial gravels, the Santa Ana sucker will go extinct in the Santa Ana River.

One goal of critical habitat designations is to recover threatened and endangered species to high enough population levels that they are no longer threatened with extinction.

Recovery requires adequate habitat so the species can increase in numbers.

Therefore the critical habitat designation for the Santa Ana sucker properly includes historically occupied habitat that currently may not host the fish, but still has all of the essential habitat components for the fish, so they can re-inhabit the area in the future.

Protecting the Santa Ana sucker in its namesake river is important and provides benefits.

The fish is a bellwether for the health of our local streams.

Suckers primarily eat algae that grow along slower flowing areas of rivers and are a prey item for predatory fishes and amphibians, fulfilling an important ecological niche in river ecology.

The sucker is a tough and resilient little fish and has survived the vagaries of the boom-and-bust hydrology of the flashy Southern California river system for eons.

Its slide toward extinction signifies a river in trouble, and because literally millions of people rely upon the Santa Ana River for water, it signifies trouble for us too.

By protecting the habitat for this remarkable fish, we not only help to staunch the worldwide extinction crisis, but ensure our precious water supplies are also protected.

- Ileene Anderson is a biologist with the Center for Biological Diversity in Los Angeles, California.